/* ====================================================================
 *
 *  Copyright 1999-2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */
package org.parosproxy.paros.network;

import java.util.Iterator;
import java.util.Vector;

import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.methods.ByteArrayRequestEntity;
import org.apache.commons.httpclient.methods.EntityEnclosingMethod;
import org.apache.commons.httpclient.methods.RequestEntity;
import org.apache.commons.httpclient.util.EncodingUtil;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * This class is basing on the HttpClient under Apache licence 2.0
 */
public class GenericMethod extends EntityEnclosingMethod {

	/** Log object for this class. */
	private static final Log LOG = LogFactory.getLog(GenericMethod.class);

	/** The Content-Type for www-form-urlencoded. */
	public static final String FORM_URL_ENCODED_CONTENT_TYPE = "application/x-www-form-urlencoded";

	/**
	 * The buffered request body consisting of <code>NameValuePair</code>s.
	 */
	private Vector<NameValuePair> params = new Vector<NameValuePair>();
	private String method = null;

	public GenericMethod(String method) {
		super();
		this.method = new String(method);
	}

	public GenericMethod(String method, String uri) {
		super(uri);
		this.method = new String(method);
	}

	/**
	 * Returns <tt>"Generic"</tt>.
	 * 
	 * @return <tt>"Generic"</tt>
	 * 
	 */
	public String getName() {
		return method;
	}

	/**
	 * Returns <tt>true</tt> if there is a request body to be sent.
	 * 
	 * <P>
	 * This method must be overwritten by sub-classes that implement alternative
	 * request content input methods
	 * </p>
	 * 
	 * @return boolean
	 * 
	 */
	protected boolean hasRequestContent() {
		LOG.trace("enter GenericMethod.hasRequestContent()");
		if (!this.params.isEmpty()) {
			return true;
		} else {
			return super.hasRequestContent();
		}
	}

	/**
	 * Clears request body.
	 * 
	 * <p>
	 * This method must be overwritten by sub-classes that implement alternative
	 * request content input methods
	 * </p>
	 * 
	 * @since 2.0beta1
	 */
	protected void clearRequestBody() {
		LOG.trace("enter GenericMethod.clearRequestBody()");
		this.params.clear();
		super.clearRequestBody();
	}

	/**
	 * Generates a request entity from the post parameters, if present. Calls
	 * {@link EntityEnclosingMethod#generateRequestBody()} if parameters have
	 * not been set.
	 * 
	 * @since 3.0
	 */
	protected RequestEntity generateRequestEntity() {
		if (!this.params.isEmpty()) {
			// Use a ByteArrayRequestEntity instead of a StringRequestEntity.
			// This is to avoid potential encoding issues. Form url encoded
			// strings
			// are ASCII by definition but the content type may not be. Treating
			// the content
			// as bytes allows us to keep the current charset without worrying
			// about how
			// this charset will effect the encoding of the form url encoded
			// string.
			String content = EncodingUtil.formUrlEncode(getParameters(),
					getRequestCharSet());
			ByteArrayRequestEntity entity = new ByteArrayRequestEntity(
					EncodingUtil.getAsciiBytes(content),
					FORM_URL_ENCODED_CONTENT_TYPE);
			return entity;
		} else {
			return super.generateRequestEntity();
		}
	}

	/**
	 * Sets the value of parameter with parameterName to parameterValue. This
	 * method does not preserve the initial insertion order.
	 * 
	 * @param parameterName
	 *            name of the parameter
	 * @param parameterValue
	 *            value of the parameter
	 * 
	 * @since 2.0
	 */
	public void setParameter(String parameterName, String parameterValue) {
		LOG.trace("enter PostMethod.setParameter(String, String)");

		removeParameter(parameterName);
		addParameter(parameterName, parameterValue);
	}

	/**
	 * Gets the parameter of the specified name. If there exists more than one
	 * parameter with the name paramName, then only the first one is returned.
	 * 
	 * @param paramName
	 *            name of the parameter
	 * 
	 * @return If a parameter exists with the name argument, the coresponding
	 *         NameValuePair is returned. Otherwise null.
	 * 
	 * @since 2.0
	 * 
	 */
	public NameValuePair getParameter(String paramName) {
		LOG.trace("enter PostMethod.getParameter(String)");

		if (paramName == null) {
			return null;
		}

		Iterator<NameValuePair> iter = this.params.iterator();

		while (iter.hasNext()) {
			NameValuePair parameter = iter.next();

			if (paramName.equals(parameter.getName())) {
				return parameter;
			}
		}
		return null;
	}

	/**
	 * Gets the parameters currently added to the PostMethod. If there are no
	 * parameters, a valid array is returned with zero elements. The returned
	 * array object contains an array of pointers to the internal data members.
	 * 
	 * @return An array of the current parameters
	 * 
	 * @since 2.0
	 * 
	 */
	public NameValuePair[] getParameters() {
		LOG.trace("enter PostMethod.getParameters()");

		int numPairs = this.params.size();
		Object[] objectArr = this.params.toArray();
		NameValuePair[] nvPairArr = new NameValuePair[numPairs];

		for (int i = 0; i < numPairs; i++) {
			nvPairArr[i] = (NameValuePair) objectArr[i];
		}

		return nvPairArr;
	}

	/**
	 * Adds a new parameter to be used in the POST request body.
	 * 
	 * @param paramName
	 *            The parameter name to add.
	 * @param paramValue
	 *            The parameter value to add.
	 * 
	 * @throws IllegalArgumentException
	 *             if either argument is null
	 * 
	 * @since 1.0
	 */
	public void addParameter(String paramName, String paramValue)
			throws IllegalArgumentException {
		LOG.trace("enter PostMethod.addParameter(String, String)");

		if ((paramName == null) || (paramValue == null)) {
			throw new IllegalArgumentException(
					"Arguments to addParameter(String, String) cannot be null");
		}
		super.clearRequestBody();
		this.params.add(new NameValuePair(paramName, paramValue));
	}

	/**
	 * Adds a new parameter to be used in the POST request body.
	 * 
	 * @param param
	 *            The parameter to add.
	 * 
	 * @throws IllegalArgumentException
	 *             if the argument is null or contains null values
	 * 
	 * @since 2.0
	 */
	public void addParameter(NameValuePair param)
			throws IllegalArgumentException {
		LOG.trace("enter PostMethod.addParameter(NameValuePair)");

		if (param == null) {
			throw new IllegalArgumentException("NameValuePair may not be null");
		}
		addParameter(param.getName(), param.getValue());
	}

	/**
	 * Adds an array of parameters to be used in the POST request body. Logs a
	 * warning if the parameters argument is null.
	 * 
	 * @param parameters
	 *            The array of parameters to add.
	 * 
	 * @since 2.0
	 */
	public void addParameters(NameValuePair[] parameters) {
		LOG.trace("enter PostMethod.addParameters(NameValuePair[])");

		if (parameters == null) {
			LOG.warn("Attempt to addParameters(null) ignored");
		} else {
			super.clearRequestBody();
			for (int i = 0; i < parameters.length; i++) {
				this.params.add(parameters[i]);
			}
		}
	}

	/**
	 * Removes all parameters with the given paramName. If there is more than
	 * one parameter with the given paramName, all of them are removed. If there
	 * is just one, it is removed. If there are none, then the request is
	 * ignored.
	 * 
	 * @param paramName
	 *            The parameter name to remove.
	 * 
	 * @return true if at least one parameter was removed
	 * 
	 * @throws IllegalArgumentException
	 *             When the parameter name passed is null
	 * 
	 * @since 2.0
	 */
	public boolean removeParameter(String paramName)
			throws IllegalArgumentException {
		LOG.trace("enter PostMethod.removeParameter(String)");

		if (paramName == null) {
			throw new IllegalArgumentException(
					"Argument passed to removeParameter(String) cannot be null");
		}
		boolean removed = false;
		Iterator<NameValuePair> iter = this.params.iterator();

		while (iter.hasNext()) {
			NameValuePair pair = iter.next();

			if (paramName.equals(pair.getName())) {
				iter.remove();
				removed = true;
			}
		}
		return removed;
	}

	/**
	 * Removes all parameter with the given paramName and paramValue. If there
	 * is more than one parameter with the given paramName, only one is removed.
	 * If there are none, then the request is ignored.
	 * 
	 * @param paramName
	 *            The parameter name to remove.
	 * @param paramValue
	 *            The parameter value to remove.
	 * 
	 * @return true if a parameter was removed.
	 * 
	 * @throws IllegalArgumentException
	 *             when param name or value are null
	 * 
	 * @since 2.0
	 */
	public boolean removeParameter(String paramName, String paramValue)
			throws IllegalArgumentException {
		LOG.trace("enter PostMethod.removeParameter(String, String)");

		if (paramName == null) {
			throw new IllegalArgumentException("Parameter name may not be null");
		}
		if (paramValue == null) {
			throw new IllegalArgumentException(
					"Parameter value may not be null");
		}

		Iterator<NameValuePair> iter = this.params.iterator();

		while (iter.hasNext()) {
			NameValuePair pair = iter.next();

			if (paramName.equals(pair.getName())
					&& paramValue.equals(pair.getValue())) {
				iter.remove();
				return true;
			}
		}

		return false;
	}

	/**
	 * Sets an array of parameters to be used in the POST request body
	 * 
	 * @param parametersBody
	 *            The array of parameters to add.
	 * 
	 * @throws IllegalArgumentException
	 *             when param parameters are null
	 * 
	 * @since 2.0beta1
	 */
	public void setRequestBody(NameValuePair[] parametersBody)
			throws IllegalArgumentException {
		LOG.trace("enter PostMethod.setRequestBody(NameValuePair[])");

		if (parametersBody == null) {
			throw new IllegalArgumentException(
					"Array of parameters may not be null");
		}
		clearRequestBody();
		addParameters(parametersBody);
	}

}
